Houston Dynamo will have eyes on results around the league on final weekend

One thing is for sure—if the Dynamo lose on Sunday in their regular season finale, they are done for the year. But beyond that, there are enough permutations to give a math professor a headache. While Houston need to take care of business at RFK Stadium, they are also relying on a little help from others to make the playoffs. Here's our guide to the matches that matter.

D.C. United vs. Houston Dynamo, 12:30 p.m. Sunday (NBC)

Nothing to play for? That concept does not exist in modern soccer. There are always consequences, always expectations. So while the standings show that D.C. are the worst team in MLS this season, with 16 points from 33 games, they will be motivated.

Some of Ben Olsen's players may be seeking to cement their places on next season's roster; D.C. will want to end the year on a high in front of their own fans; and no one will have forgotten that last season the Dynamo beat United in the Eastern Conference playoff final. Plus, an eliminated team has the freedom to enjoy itself against opponents in tense situations, and that often shows in the pattern of play.

"The one year that we didn't make the playoffs [2010] I think we won our last couple of games. It was just nothing-to-lose soccer, a lot of new guys out there getting a chance to show," Dynamo—and ex-United—defender Bobby Boswell said earlier this week.

"We knocked them out of the playoffs last year, what better redemption than to knock us out? But that's their job, you get paid to win the game. And we're going to go out there and try to get a result, move on, be back in the playoffs, that's where we want to be."

Captain Brad Davis was also wary of D.C. when it was pointed out to him last Sunday that the Dynamo have beaten them twice this season. "Just saying 'we beat them twice' and saying 'we're playing D.C., we should win this game', doesn't mean we will win. We still have to come out, prepare well, have the right mentality.

"Sometimes it's the most difficult to play a team that has nothing to lose. The might have guys out there trying to prove a point, trying to make the team possibly for next year, prove to their coach they belong on the team, and sometimes that can be some of the most difficult teams to play against. So it's definitely going to be a rough game for us and we will need to go in there and get a win.

"I still feel like we'll get a good chance if we go in and beat D.C. next week, I think we'll get in to the playoffs, but you don't know—we'll see what happens. We know that we can do it, we've been there a couple of times, there's no reason to think we can't."

In seventh, two points below the Dynamo, the Union have to win to have any chance of reaching the top five. A Union victory and a Dynamo draw would (almost certainly) put Philadelphia above Houston on the goals scored tiebreaker.

The Union are without their captain, defensive midfielder Brian Carroll, who is suspended. He had started all 33 of their MLS games this year. The Union lost 3-1 to SKC at PPL Park on the opening day of the season but beat them on the road last month.

An SKC side mostly comprised of first-team regulars drew 0-0 with CD Olimpia at Sporting Park on Wednesday to confirm their passage into the next stage of the CONCACAF Champions League. With SKC head coach Peter Vermes not making his first substitution until the 79th minute, it seems he was unworried about possible fatigue coming into this Saturday's game.

SKC are on a four-match unbeaten run in all competitions and have not given up a goal in that spell, though they've scored only twice. SKC can finish no lower than second, but there is still plenty to play for: one point behind the New York Red Bulls and Real Salt Lake in the chase for the Supporters Shield, SKC need to win to have any hope of finishing with the best record in MLS.

Toronto FC vs. Montreal Impact, 3 p.m. Saturday (MLS Live)

The Impact are one point ahead of the Dynamo and looking for a win that would almost certainly see them claim third place. If Houston and Montreal end up level on points the Quebec club will finish above the Dynamo on tiebreakers.

Toronto, meanwhile, are second-bottom in the Eastern Conference with a mere 26 points from 33 games and only 29 goals scored. But they are tough to beat at home, where they have drawn half their fixtures and lost only five times—the same amount as SKC and the New England Revolution.

This will be the fifth meeting of the Canadian rivals this year but there is no discernible pattern to the results. The Impact won 2-1 at home in March, there was a 3-3 draw at BMO Field in July, and the teams clashed in the semi-finals of the Canadian Championship. Toronto won the first leg 2-0 but lost the return 6-0. As an MLS club, the Impact have never won in Toronto in four attempts.

Until last week's 2-1 win over Philadelphia, Montreal were enduring a run of five defeats and one draw in their past six MLS games. But they have a lethal target man in Marco Di Vaio, who is joint-top goalscorer in MLS this year with 20 strikes.

Columbus Crew vs. New England, 3 p.m. Sunday (MLS Live)

The Revolution are fifth, level on points with the Dynamo and level on the first tiebreaker (wins) but ahead by virtue of having scored nine more goals.

What does familiarity breed? We're about to find out, since, oddly enough, these clubs are meeting for the second time in eight days. Last weekend a 76th-minute winner from Diego Fagundez gave the Revolution a 3-2 win at Gillette Stadium that officially ended the Crew's postseason hopes. In a wild game, New England took the lead twice, only for Columbus to hit back.

The Revolution beat Columbus 2-0 at Crew Stadium back in July with two goals in stoppage time. New England have won three and drawn two of their past five MLS matches and have not failed to score since going down 3-0 to SKC back on August 10.

New York Red Bulls vs. Chicago Fire, 4 p.m. Sunday (UniMas)

Chicago are fourth, one point clear of Houston and holding the edge on tiebreakers.

After last Sunday's costly defeat at BBVA Compass Stadium, the Dynamo are now hoping the Red Bulls will do the Men in Orange a huge favor at a sold-out Red Bull Arena.

Chicago have won their past three games, albeit against teams that are out of contention—D.C., FC Dallas and Toronto. Their slow start to the campaign long forgotten, Frank Klopas' team have lost only two of their past ten games.

Mike Magee has scored in his past two appearances and is tied on 20 goals with Di Vaio in the Golden Boot race. With 14 goals in 21 MLS starts since leaving the Los Angeles Galaxy for his native Illinois, the forward is crucial to the Fire's prospects. But they will be without stalwart midfielder and vice-captain Jeff Larentowicz, who is suspended.

New York are certain to claim the Supporters Shield if they win, and a draw may be enough—but they cannot win the prize if they lose. Since SKC play a day earlier, Mike Petke's team will kick off knowing exactly the result they require. The Red Bulls have the best home record in the East: ten wins, four draws, only two defeats. They lost 3-1 to Chicago at Toyota Park in April.

Tom Dart is a contributing writer to HoustonDynamo.com. Former editor and reporter for The Times of London, Dart currently freelances for The Guardian and SI.com.